Additive manufacturing methods may include 3D printing techniques such as selective laser sintering or selective laser melting in which a 3D part is produced layer by layer by irradiating with a laser beam a powder bed of material contained within a chamber. Selective laser sintering uses a laser to sinter material together. Selective laser melting is similar but uses a laser to fully melt (rather than sinter) the material together, thus allowing for different properties such as crystal structure, porosity and the like. As used herein selective laser sintering and selective laser melting may be referred to, collectively, as “Selective Laser Fusing.” Similarly, as used herein, sintering and melting may be collectively referred to as “Fusing” or “Fuse” or “Fused.”
For Selective Laser Fusing, the digital representation of the 3D part is sliced into multiple (typically horizontal) layers. For each sliced layer, a path is generated along which the laser beam selectively moves to Fuse powdered material spread across a bed of material in a chamber. After each layer is completed, the bed of powdered material is lowered by one layer thickness, a new layer of powdered material is applied on top of the bed, and the process is repeated until the part is completed.
Parts, and in particular relatively large diameter contoured or annular parts, with relatively thin cross-sections may be difficult to manufacture using conventional methods. For example, an annular part such as a duo-cone seal (face seal) that has a large diameter and a thin cross-section may be difficult to manufacture using conventional methods. While such a part may benefit from additive manufacturing that uses 3D printing techniques such as selective laser sintering or selective laser melting, the large diameters of such parts make the use of such techniques difficult to implement on a production scale while maintaining consistency and quality for the part.
US Publication No. 2013/0264750 discloses a method and a device to perform selective laser sintering. The device includes a rotatable powder delivery unit and a stationary laser. Mirror mechanisms are used to deflect the laser beams to guide the laser beams over the surface of the powder bed. While beneficial, a better system is needed.